讲座内容：

In this talk, we classify 1-cocycles of the Witt algebra with coefficients in the tensor product of two arbitrary tensor density modules.

In a special case, we recover a theorem originally established by Ng and Taft. Furthermore, by these 1-cocycles, we determine Lie bialgebra structures over certain infinite-dimensional Lie algebras containing the Witt algebra. This is a joint work with Shoulan Gao and Dong Liu.